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<A HREF="contents.html"><IMG TITLE="Programming in Lua (first edition)" SRC="capa.jpg" ALT="" ALIGN="left"></A>This first edition was written for Lua 5.0. While still largely relevant for later versions, there are some differences.<BR>The third edition targets Lua 5.2 and is available at <A HREF="http://www.amazon.com/exec/obidos/ASIN/859037985X/theprogrammil3-20">Amazon</A> and other bookstores.<BR>By buying the book, you also help to <A HREF="../donations.html">support the Lua project</A>.
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<font color="gray">Programming in </font><font color="blue"> Lua</font>
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<td width="80%" align="center"><a href="contents.html#P1">Part I. The Language</a>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
<a href="contents.html#3">Chapter 3. Expressions</a></td>
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<p><h2>3.1 &ndash; Arithmetic Operators</h2>
Lua supports the usual arithmetic operators:
the binary `<code>+</code>&acute; (addition), `<code>-</code>&acute; (subtraction),
`<code>*</code>&acute; (multiplication), `<code>/</code>&acute; (division),
and the unary `<code>-</code>&acute; (negation).
All of them operate on real numbers.

<p>Lua also offers partial support for `<code>^</code>&acute; (exponentiation).
One of the design goals of Lua is to have a tiny core.
An exponentiation operation
(implemented through the <code>pow</code> function in C)
would mean that we should
always need to link Lua with the C mathematical library.
To avoid this need, the core of Lua offers only the syntax for the
`<code>^</code>&acute; binary operator,
which has the higher precedence among all operations.
The mathematical library (which is standard, but not part of the Lua core)
gives to this operator its expected meaning.

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  Copyright &copy; 2003&ndash;2004 Roberto Ierusalimschy.  All rights reserved.
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